Sheet stacking and transfer mechanism



July 16, 1940. R. R. SEFT SHEET STACKING AND TRANSFER MECHANISM 2Sheets-Sheet 1 Filed July 11, 1939 July 16, 19%. R R EFT 2,208,433

SHEET STACKING AND TRANSFER MECHANISM Filed July 11, 1959 2 Sheets-Sheet2 J2 llIIIIlllI|IIIIIIIIIIIIIIIIIIIIIIIIIII 33 J 01 e Ta \i 5L D] r 1ZQ/LIT 6 a 2/ I b 2 INVENTOR Patented July 16, 1940 PATENT GFFICE SHEETSTACKING AND TRANSFER MECHANISM Rudolph R. Seft,

Brackenridge, Pa.

Application July 11, 1939, Serial No. 283,805

3 Claims.

This invention relates to new and useful improvements in sheet stackers,more particularly to a stacker for conveying sheet material from areceiving station and transferring the same to a delivery station in amanner to eliminate relative movement between the sheet and its support,thereby preventing marring and scratching of the surface, the inventionbeing particularly useful in the handling of highly polished metalsheets such as stainless steel or chromium plated materials.

The invention will become more apparent from a consideration of theaccompanying drawings constituting a part hereof in which like referencecharacters designate like parts and in which:

Fig. 1 is a top plan View of a sheet transfer mechanism embodying theprinciple of this invention;

Fig. 2 a side elevational View thereof;

Fig. 3 an end elevational View taken on line 33, Fig. 2; and

Figs. 4 to '7 inclusive, diagrammatic illustrations of the conveyingmeans in the positions of receiving and delivering the sheet material.

In the several figures of the drawings, the numeral l designates a pairof side frames mounted on a base 2 having an elevated rail 3 boltedthereon by clamping brackets 4 constituting the rail 3 a rigid extensionof the side frames. The side frames are connected by tie rods 5 and 6bolted at their ends and in between the frames in the manner shown inFig. 3 so that the assembled frames on their bases 2 constitute aself-sustaining machine unit, which is readily transportable for use todifferent sections of an industrial plant.

Mounted on the rails 3 is a shuttle frame 1 supported on wheeled axles8, the wheels 9 of which ride the rail 3 between the rail stops or endabutments I and II. Wheels 9 are flanged wheels as shown in Fig. 1 toprevent displacement of the shuttle frame on its supporting rail whensubjected to shuttle movement. The frame 1 is provided with gear teethI2 along their entire length which constitute the frames 1 gear racksthat are engaged by the teeth 13 of gear wheels 14 mounted on a commonshaft l having a pinion l6 that is actuated by a rack l1.

Rack H is mounted on a flanged guide wheel l8 which is spaced frompinion I6 a suitable distance to maintain proper contact of the rackteeth with the pinion teeth. Back I! is further provided with anelongated slot l9 in which is disposed a drive shaft that carries acollar 2| to prevent displacement of the rack. The rack is furtherprovided with rollers 22 and. 23 which engage a driver 24 that ismounted to rotate with the shaft 20 to constitute an eccentric drive.

As shown in Fig. l, shaft 20 is driven through gear train 25 by themotor 26 and when the motor is energized the eccentric movement of thering 24 engaging rollers 22 and 23 causes a reciprocating movement ofthe rack drive H which subjects the shuttle frame 1 to reciprocatingmovement on the track 3 within the limits of the stroke of rack l1.

The sheet material to be transferred on the shuttle frame is supportedby a plurality of belts 21 that extend over roll shafts 28 and 29, theshafts being journaled on the shuttle frames 1.

Frames 1 are provided with tie rods 30 and 3| to rigidly secure them,and are further provided with tongues disposed in slots 32 and 33 of therails 3, Fig. 3, to prevent upward displacement of the rack. The belts21 pass around a series of flanged pulleys 34 and around a plurality ofpulley shafts 35 and 36 that are journaled on the main frames I.

There are a plurality of belts, a series of five sets of belts beingshown, which pass around the pulleys of shafts 28, 29, 35 and 36, in themanner shown in Figs. 1 and 4 to '7 inclusive.

The pulley shafts are actuated by drive mechanism separate from theshuttle frame drive and consists of a train of gears generallydesignated by the reference numeral 31, driven from shaft 38 of themotor 26, there being two power shafts extending from a geartransmission which is housed in the end bracket 39 of a motor 26. Onlythe shaft 36 is driven by the gear train, and shafts 28, 29 and 35 areactuated by the belt as driven by shaft 36. i

The operation of the sheet transfer and. stacking mechanism is moreclearly shown in connection with the diagrammatic illustration of Figs.4 to 7 inclusive of the drawings and is as follows:

The transfer apparatus is mounted at a receiving station such as cuttingshears, roller levels or other apparatus employed for acting upon thesheet material, such as highly polished monel metal or chromium platedsheets in a manner to support the sheet flatwise as it is dropped bodilyon the belts 21. The shuttle mechanism is continually operative in itstraversing movement across the rails 3 between the abutments I0 and Hand is in timed relation with the dropping of the sheet material on thebelt, so that when viewed in the drawings the shuttle frame 1 would bein the extreme right hand position of its travel as the sheet is droppedthereon. The shuttle drive is effected through the eccentric ring 24which actuates the rack I! that in turn rotates gear wheels I3, which bytheir rack-tooth engagement with the shuttle frame subject the latter tothe shuttle or traversing movement on the rails 3.

Simultaneously with the movement of the shuttle frame, the gear drive 31actuates all of the belts 21 so that the belt movement will be in thesame direction as the shuttle movement, and the sheet material, whichisreceived on the belt when in the extreme right hand position, as shownin Fig. 4 of the drawings, the numeral designating the sheet material,will be moving in the same direction as the shuttle, as shown by thearrow, but at a faster rate, so as to traverse the distance betweenrollers 28 and 29 while the shuttle frame is travelling toward theextreme left hand abutment H.

As the shuttle frame reaches the end of its travel, the sheet 49 willhave passed beyond the end of the belt and the tip of the sheet willrest on top of the stack so that upon beginning of the reverse movementof the shuttle and the belt running forward, it will be dropped ofi asshown in Fig. 7 of the drawings. By this combined movement of theshuttle and belts, there is no relative movement between the sheetmaterial and its support, or any part of the transfer mechanism, thuspreventing the marring orscratching of the surface of the sheet, whichis laid upon the stack as though placed thereon by hand.

Upon reverse movement of the carriageafter the sheet has been depositedon the, stack, the

top flight of the belt will be substantially stationary or movingslightly in the opposite direc-' tion from the movement of the carriage.If, therefore, a plurality of sheets have been deposited on the topflight in axially spaced relation, the second sheet will remain on thecarriage and a second sheet will be deposited thereon when the carriagereturns to the receiving station.

Although one embodiment of the invention has been herein illustrated anddescribed, it will be obvious to those skilled in the art that variousmodifications may be made in the details of construction withoutdeparting from the principles.

herein set forth.

I claim:

1. Apparatus for transferring sheet material and the like comprising asupporting base structure, a movable frame supported on parallel railsof said structure, a plurality of pulleys mounted on said frame, and aplurality of pulleys mounted on said supporting structure, conveyorbelts looped around said pulleys, means for subjecting said frame toshuttle movement on its support, and independent means for actuating thebelt pulleys to subject the belt to movement simultaneously with and inthe direction of sheet transferring movement of the shuttle frame.

2. Apparatus for transferring sheet material comprising a plurality ofparallel side frames mounted on a base having transverse supportsconstituting a rigid supporting structure, a plurality of rails on saidframe, a carriagelmounted on wheeled axles movable on said rails, saidcarriage being provided with rack teeth for engagement with gear wheels,a rack arm for actuating the gear wheels, an eccentric drive for saidarm to subject the carriage to reciprocating movement on the rails,pulley shafts mounted on the carriage and pulley shafts mounted in theside frames for supporting endless conveyor belts, means for actuatingthe pulley shafts to drive said belts whereby the belts and carriagesimultaneously travel in the same direction during the sheet transfermovement of the carriage.

3. Apparatus for transferring sheet material comprising a plurality ofparallel side frames mounted on a base having transverse supportsconstituting a rigid supporting structure, a plurality ofrails on saidirame,a carriage mounted on wheeled axles movable on said rails betweena receiving station and a delivery station, a plurality of pulley shaftsmounted in said carriage and side frames, endless belts passing aroundthe pulleys of said movable carriage and side frames, means foractuating the belts, and means for actuating the carriage tosimultaneously subject the belt pulleys and carriage to movement in thesame direction while the carriage is travelling from the receivingstation and to maintain the top flights of the'beltsubstantiallystationary upon the reverse travel of said carriage.

RUDOLPH R, SEFT.

